WASHINGTON, Jan 30 (Reuters) - The mercury in a vaccine preservative is pumped out of a baby's body too quickly for it to do any damage, researchers reported on Wednesday in a study they say should further absolve shots of causing autism.

The study in the journal Pediatrics reinforces what many vaccine experts have said for years -- that the form of mercury found in the preservative is handled differently by the body than the kind found in pollution and contaminated fish.

... Pichichero's team studied 216 infants from R. Gutierrez Children's Hospital in Buenos Aires, Argentina, where thimerosal is still routinely used in vaccines.

They were divided into three age groups to have their blood-mercury levels tested before and after they were immunized at their newborn, 2- or 6-month checkups.

Blood tests showed the half-life of ethyl mercury -- the time it takes for the body to dispose of half of it -- was 3.7 days. The more dangerous methyl mercury, known to damage nerves, has a half-life of 44 days.

I recently read that Dr. Sears is now focusing on a different vaccine additive -- aluminum -- as a possible autism factor. Is that going to be the new mercury?